The present invention is directed to an apparatus for non-contacting disintegration of calculi in the body of a patient which apparatus comprises means for emitting a focused shock wave in a fluid-filled shock wave tube which is closed at its application side by a flexible membrane which is pressed against the patient and yields because of the fluid pressure in the tube.
An apparatus of the above type is employed for the disintegration of kidney stones. With the assistance of an X-ray means, the spatial position of the kidney stone can be located and the shock wave source can then be aligned relative to this kidney stone so the focal point for the shock wave source lies in the kidney stone. The kidney stone disintegrates due to the generation of a plurality of shock waves and the pieces are then eliminated in a natural way from the body of the patient.
It is necessary for an effective calculus disintegration that the location of the focal point of the shock wave source lies approximately in the center of the calculus. In addition to an exact location of the calculus, it is also required for this purpose that the position of the focal point of the shock wave source be precisely known. In practice, this means that the position of the focal point must lie at a prescribed, three-dimensional location in front of the shock wave source.